Ars Technica is reporting that certain 64bit Mac models won't be able to run Mountain Lion. The problem is the graphic card drivers; these are still 32bit, and Apple is unwilling to update them to 64bit. A 64bit kernel can't load 32bit drivers, so that's that. Apple has a list of supported models on their Mountain Lion upgrade page, so you can easily check if your computer is capable of running Mountain Lion.

The real issue here isn't whether a machine can run a new OS, but that the old OS will stop receiving security updates relatively shortly. If the next release is also 12 months, and if Apple continues with its current N-1 support policy, a Core 2 Duo won't have any updated Mac OS 12 months from now. The hardware will still be perfectly capable at that time, and presumably will still be in widespread use.

Based on what evidence? Apple has said why support has been dropped - the lack of EFI64 firmware so why do you automatically assume they'll drop support for Core 2 computers? for what reason? what purpose? I'm going to book mark your post and lets see what happens in 12 months time when the next version is released.